How Do You Correctly Name Chemical Complexes?

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Discussion Overview

The discussion revolves around the correct naming of various chemical complexes, focusing on the rules of nomenclature for coordination compounds. Participants explore different naming conventions and the implications of charge and ligand types in their proposed names.

Discussion Character

  • Technical explanation
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • One participant presents a list of chemical complexes and expresses uncertainty about their naming, referencing specific rules for order, prefixes, oxidation states, and suffixes.
  • Another participant suggests names for the complexes, indicating uncertainty with phrases like "I think..." and "All just guesses." They propose names such as "tetrachlorocuprate (II)" and "diaminosilver (II)."
  • A later reply corrects a formula, suggesting that Al(H2))6Cl3 should be Al(H2O)6Cl3 and proposes names like "aluminium chloride hexahydrate" and "hexa-aquaaluminate chloride," while questioning the naming of other complexes.
  • Another participant provides detailed explanations for their proposed names, discussing the order of ligands, the significance of charges, and the use of "-ate" suffixes for negative complexes. They suggest names like "tetraamminecopper (II)" and "trichlorohexaaquoaluminum (III)," while also addressing the implications of the charges on the naming conventions.

Areas of Agreement / Disagreement

Participants express differing views on the correct names for the complexes, with no consensus reached. There are multiple competing suggestions and interpretations of the nomenclature rules.

Contextual Notes

Participants reference specific rules and conventions for naming coordination compounds, but there are unresolved questions about the accuracy of certain names and the interpretation of the chemical formulas presented.

msdel
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I must name these substances

a) [Cu(Cl4)]^2-
b) Ag(NH3)2+
c) Cu(NH3)4SO4-
d) Al(H2))6Cl3


Now I have read the rules regarding naming these,
-Within the brackets the order- negative-charge, neutral and central.
-The number of each ligand is indicated by greek prefixes
-oxidation state of central ion as roman numeral
-if the complex species is negative, the name of the central atom ends with the suffix-ate.

As far as I am concerned I have come up with some rather creative names for these. I don't think I am doing it right, some help understanding this would be great!
 
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a) tetrachlorocuprate (II)
b) diaminosilver (II) (I think...)
c) tetraaminocupricsulphate (spaces? hyphens?)
d) hexahydrogenaluminumchloride (?)

All just guesses :P
 
Nerro said:
d) hexahydrogenaluminumchloride (?)

All just guesses :P

No, d) Al(H2))6Cl3 should definitely be d) Al(H2O)6Cl3 which means I think it is just hydrated aluminium chloride AlCl3.6H2O (aluminium chloride hexahydrate). But if that's not the same thing, then I'd have to call Al(H2O)6Cl3 hexa-aquaaluminate chloride.

I think b) is ammono not amino. amino is something organic to me.

Shouldn't c) then be tetraammonocopper sulphate? (If the - sign is wrongfully there - Otherwise I don't know - tetraammonocopper(I) sulphate? Is this an ion?? Should we even call it monosulphate?)
I think tetraammonocupric sulphate would be the salt [Cu(NH3)4]2SO4.
 
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Nomenclature

The names should be:

a) [Cu(Cl4)]2-
tetrachlorocuprate (II) ion
because the chlorine is a negative atom, so its named first, and there is no neutral atom so the central ion (the positive atom) is named second and since the charge difference between the four chlorines (4-) and the actual charge of the molecule is 2+, that means the copper has (II) in its name. The total charge is negative so you add "-ate" to the end, and you get cuprate (because you use the latin part of the name for this so it wouldn't be, say, ironate but ferrate).

b) Ag(NH3)2+
diamminesilver (II) ion
because there is no negative atom, and there is a neutral one ((NH3)2) and there is two of them, so ammine turns into diammine (and its spelled correctly, I checked). The next atom is the central one and so we name it silver, and since the charge of the molecule is 1+ and the charge of ammonia is 0, the charge of the silver molecule must be 1+, hence the silver (I) part. This is not a negative compound so there is no "-ate" added.

c) Cu(NH3)4SO4 (a neutral compound)
Monosulfatetetraamminecopper (II)
because we are supposed to name the stuff in brackets first, but since there are no brackets, we don't separate the names. First comes the negative ligand (one sulfate so its monosulfate), then the netural one (four ammonias so its tetraammine - having the two "a"s in the name beside each other doesn't matter), and then the central ion (the positive one - in this case, copper and since the neutral ligand has no charge, while there is a charge of 2- from the sulfate, that means it is followed by (II)).

d) Al(H20)6Cl3 (a neutral compound)
Trichlorohexaaquoaluminum (III)
because there are no brackets, we include the chlorine in the naming. First name the negative ligand (Cl3 so its trichloro) then the neutral ligand (six times H20 so its hexaaquo) and lastly the central ion (aluminum and since the charge of the compund is zero, the charge of the neutral ligand is zero, and the negative charge of three chlorine atoms is 3-, then aluminum is followed by (III) for a 3+ charge).
 
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